#include <iostream>
#include <fstream>
#include <cmath>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n,m,t[100001],x,y,sqr,p[100001],l[100001],nr=1,max1;
void dfs (int cur)
{
    if (l[cur]<max1)
    {
        p[cur]=1;
    }
    else if (l[cur]%max1==0)
        p[cur]=t[cur];
    else p[cur]=p[t[cur]];
    for (int i=1; i<=n; i++)
    {
        if (t[i]==cur)
            dfs(i);
    }
}
int lca (int a,int b)
{
    while (p[a]!=p[b])
    {
        if (l[a]>l[b])
        {
            a=p[a];
        }
        else b=p[b];
    }
    while (a!=b)
    {
        if (l[a]>l[b])
        {
            a=t[a];
        }
        else b=t[b];
    }
    return a;
}
int main()
{
    f>>n>>m;
    sqr=sqrt(n);
    l[1]=1;
    for (int i=2; i<=n; i++)
    {
        f>>t[i];
    }
    while (nr<n)
    {
        for (int i=2; i<=n; i++)
        {
            if (l[i]==0)
            {
                if (l[t[i]]!=0)
             {

             nr++;    l[i]=l[t[i]]+1;
             max1=max(max1,l[i]);
            }
            }
        }
    }
    dfs(1);
    for (int i=1; i<=m; i++)
    {
        f>>x>>y;
        if (x<y)
        g<<lca(x,y)<<'\n';
        else g<<lca(y,x)<<'\n';
    }
    return 0;
}